Guide

How WhirlBiotic works.

WhirlBiotic uses Bacillus Ferment as part of a regular hot-tub care routine. Here you will find dosing, application, ingredients, and the important limits compared with required sanitation.

Hot tub with crystal-clear water and gentle steam in soft morning light
The science

What Bacillus ferment actually does in your water.

  • 01

    Safety class 1, non-pathogenic.

    Bacillus cultures occur naturally in soil and water. The strains used in WhirlBiotic are classified worldwide as ATCC Biolevel 1 — safe for people and pets.

  • 02

    They colonize surfaces.

    The cultures grow on tub surfaces, inside pipework, jets and on filters. There they metabolize organic residue — skin oils, sweat, body care products — that would otherwise feed harmful bacteria and let organic deposits form.

  • 03

    They don't replace mandated hygiene.

    Where chlorine or bromine is required by law, WhirlBiotic doesn't replace it. It reduces the organic load so you can maintain stable water with much smaller amounts.

Macro shot of water with light refractions and fine particles
Application

Step by step.

Start phase — the first 3 days

On three consecutive days, add 30 ml of WhirlBiotic to the water. Shake well before use.

Day 1
Dose 30 ml WhirlBiotic
Day 2
Dose 30 ml WhirlBiotic
Day 3
Dose 30 ml WhirlBiotic

Weekly care

From day 4 onward, dose once per week — the amount depends on your water volume. If the spa is used several times per day, also dose an additional cap of WhirlBiotic after each bath. See the dosing table below. Dosing table ↓

For every dose
  • Add to the water while the massage pumps are running.
  • Keep the pumps running for at least 20 seconds afterwards.
  • Don't pour directly onto the filter.
Hands pouring a measured dose of WhirlBiotic into bubbling spa water
Dosing

Weekly dose by water volume.

Weekly dosing by water volume
Water volumeCare dose (weekly)
Up to 1 m³30 ml
Over 1 – 2 m³50 ml
Over 2 – 4 m³100 ml
Over 4 – 6 m³150 ml

Not sure how much water your hot tub holds? Check the manual, or roughly calculate length × width × depth (in meters).

Calculate your dose
Storage & safety

Storage and safety notes.

Storage

  • Keep in the original packaging, sealed.
  • Store between 5 °C and 35 °C.
  • Protect from direct sunlight.
  • Do not freeze.

Safety

  • Keep out of reach of children.
  • If medical advice is needed, have the packaging or product label available.
  • Contains only Safety Class 1 microorganisms (non-pathogenic).
Ingredients

Four ingredients. Nothing more.

  • 01

    Aqua

    Water as the carrier medium — the base of the formulation.

  • 02

    Bacillus Ferment

    The probiotic active. Safety Class 1 cultures, non-pathogenic.

  • 03

    Phenoxyethanol

    Mild preservative, ensures stability and shelf life.

  • 04

    Ethylhexylglycerin

    Co-preservative, skin-friendly.

Close-up of the WhirlBiotic bottle on a neutral surface
Application FAQ

What customers ask most often.

What if I miss a weekly dose?

No problem. Resume with your next regular weekly dose — you don't need to double-dose. After a longer pause (several weeks), we recommend a shorter start phase.

Can I still use chlorine or bromine?

Yes. WhirlBiotic is compatible with reduced amounts of chlorine or bromine. Very high spikes can temporarily suppress the cultures — once they subside, the microbiome rebuilds itself. Where chlorine or bromine is legally required, WhirlBiotic does not replace it.

How long does a 1 L bottle last?

For a hot tub up to 1 m³ at the standard 30 ml weekly dose, one bottle covers about 33 weekly applications — roughly eight months of care after the start phase.

Do I need to change the water before starting?

No. WhirlBiotic works with your existing water. Ideally, clean the filter and balance the water chemistry before the start phase.

What if the water isn't clearer after 24 hours?

Check the filter, water chemistry, and whether the dose matches your water volume. Full biological effect builds over one to two weeks — early effects (softer feel, less odour) are usually noticeable much sooner. If you don't see any change after two weeks, contact support.

Ready for living water?

Pick a bundle that matches your routine — or read first why WhirlBiotic is different from traditional chemistry.

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